Leo daft



v(No Model.)

L. DAFT.

ELECTRIC MOTOR.

Patented May 23, 1882.

Im) emo?. 'Leo- 3a, My

Witnesses.

JZiZys.

. UNITED STATES PATENT QEEICE.

LEO DAFT, OFGREENVILLE, NEW JERSEY.

ELECTRlC MOTOR.

SPECIFICATION forming part of Letters Patent No. 258,383, dated May 23,1882.

Application filed January 2S, 1882. (No model.)

To all whom it may concern:

Be it known that I, LEO DAFT, a subject of the Queen ot Great Britain,residing at Greenville, in the county of Hudson and State of New Jersey,have invented new and useful Improvements in Electric Motors, ofwhich the following is a specification.

This invention relates to a devicefor imparting a reciprocating motionto a metallic rod by the action of electricity; and the inventionconsists in the combination of two axial inagnets, a soft-iron corecommon to both, and a eommutator which is actuated by the core so as toclose an electric circuitalternately through the helices of the axialmagnets, thereby imparting to the core a rapid reciprocating motion.With the axial magnets is combined a frame which moves on suitableguides and isadjusted by a feed-screw.

This invention is illustrated in the accompanying drawings, in whichFigure 1 represents a vertical section of my invention. Fig. 2 is a sideview of the mechanism for imparting to the core a revolving motion. Fig.3 is a horizontal section of the same in the plane m, Fig. 2.

Similar letters indicate corresponding parts.

In the drawings, the letters A B designate two axial magnets, which areplaced in line with each other, and which have a common soft-iron core,C. On this core are secured two rings, a b, by means of set-screws c d,and if the core moves up and down these rings serve to actuate thecircuit-ch an ger e, which slides on a metallic rod, f, and embracesasectional rod, g h, the two sections of which are connected by ahard-rubber section, i, or by any other suitable insulating materials. Drepresents a battery or any other suitable generator of electricity,suchas a dynamo-electric machine, and the connections between this generatorotelectricity and the several parts oi'l my device are as follows: Themetallic rod j" connects by a wire, 10, with one-say the negativepole ofthe generator. The other (positive) pole of the generator connects by awire, l1,with one end ofthe helix A, and the other end of this helixconnects by a wire, 12, with the section 7L ot' the sectional rod g h.The positive pole of the generator also connects by a wire, 13, with oneend of the helix B, and the other end of this helix connects by the wire14 with the section g ofthe rod g 711.

In the position shown in the drawings the circuit is closed through thehelix A by wires Il and 12, circuit-changer c, rod f, and wire 10, thecore C moves upward, the circuit-changer c is carried up so as toembrace the section g ot' rod g h, the circuit through helix Ais brokenand that through helix B is closed, (wires 13 la, circuit-changer e, rodand wire 10,) the core C moves downward, the circuit-changer is carrieddown to the position shown in the drawings, and so on.

In order to secure the best ei't'ects it is desirable that the soft-ironcore G should be somewhat shorter than the distance between the twoouter flanges of the axial magnets A B. Atthe same time it is necessarythat the core should be properly guided throughout the entire lengthot'its stroke. This purpose Ieffect by applying to both ends of the coreextensions F F, which are made of some non-inagnetic metal-such,forinstanee, as phosphor bronze-equal in diameter to the core andconnected to the same by screw-nipples 7c, as shown in the drawings, orby other suitable means.

The two axial magnets A B are secured in a frame, G, which moves insuitable guides, H, and which can be adjusted bya screw, I. For thispurpose the i'rame G is provided with a yoke, J, to engage with the endof the screw, and the guides II are connected by a cap or cross-bar, K,which is tapped to correspond to the thread of said screw. Thisarrangement is desirable if my device is used for operating arock-drill, in which case the drill is secured to the lower extension Fofthe core, and as the work progresses the frame G is gradually feddownward. At the same time the rockdrill has to be turned at'ter eachstroke, and for this purpose I apply a suitable devicesuch, forinstance, as shown in the drawings. This device consists ofthe anges mm, which are firmly secured to the upper extension F ofthe core C, andwhich act on the arm n ot' a bell-crank lever, u o, that has its fulcrumon a pivot, j), secured in a standard, q, which is fixed to the frame G.The arm o ot' said bellcrank lever engages with aring, e, which turns onthe extension F and carries a pawl, r, which ICQ

